I would suggest doing a compression check and see what the condition of the motor seems to be.
I bought my 71 that has a 350 in it an about 2 months later was burning lots of oil and fouling plugs. I took out the motor and put new crank and rod bearings, new oil pump and honed the cylinders, put on new piston rings and put it back together. Not a top notch rebuild but it solved my problem.
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1971 Chevy 1/2t, 350
1998 Yamaha V-Star 650
1970 Chevy 3/4t, I6(freshly rebuilt), 4 speed
Keokuk,IA
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